1. Field of the Invention
The invention relates to an upper valve part for fittings, having a head piece through which a spindle passes, and means for shut-off, and having a seal that comes to rest on the fitting.
2. The Prior Art
The exit of media from fittings is controlled using upper valve parts. For this purpose, the upper valve part is screwed into the housing of a fitting by its head piece, and a handle or lever is set onto its spindle. In the case of known upper valve parts (see German Patent Nos. DE 32 07 895 C2, DE 36 38 180 C2, and DE 87 15 044 U1), two disks for controlling the through-flow are provided, in each instance. The disks are produced from ceramic material. One of the two disks, the control disk, is disposed to rotate in the upper valve part, using a driver that is connected with the spindle. The other disk, the inlet disk, is a fixed valve seat disk, also referred to as a fixed disk. When the control disk is rotated, the disks slide on one another. On the side facing the valve seat of the fitting, a seal is disposed, which rests against the inlet disk. The seal projects beyond the face of the upper valve part. It serves as a seal both towards the inlet disk and towards the valve seat of the fitting.
Furthermore, an upper valve part for fittings is known from German Patent No. DE 200 08 679 U1, in which shut-off is achieved in that the control disk automatically changes from its position in which it allows through-flow to its shut-off position, subsequent to a pulse. Therefore, the upper valve part allows only two activation positions, namely the position “completely open” and the position “completely closed.” Activation of the upper part takes place by means of pressing on a cap, counter to a spring. In this way a blockage exerted on the handle is released. The handle can then be turned. The rotation of the handle is transferred to the spindle, thereby opening the valve. Activation into the closed position takes place in comparable manner.
The known upper valve parts fulfill all the tasks set for them. However, the design effort is quite complicated, because of the requirement of a handle that can be moved in the axial direction of the upper valve part, as well as the mechanism for shutting off the valve. As a consequence, the production of the upper valve part is complicated.